Hi Geek! There was a family in the congregation (actually a big extended family spread over several congs) that your description reminds me of. These people were so sure they were right about everything and would never let anybody get a word in. They were like jackhammers. They were the worst when talking to JW brothers and sisters. There was nothing like a conversation, just override with their irrefutable wisdom.
Nobody wants to be around people like that. It got so, if I saw them out in public I would wave and run the other way. The last time I saw one of them and they were calling after me, didn't I want to hear about this or that, I hollered NO over my shoulder as I ran the other way.
It's intimidation, and as Narcissistic would say, it's narcissisism (can't spell it) - people just FULL of themselves.